Earlier this summer Major League Baseball announced that it would be tightening up and enforcing its ban on foreign substances for pitchers, in an effort to stimulate offense. The official MLB memo announcing the crackdown came out June 15th, but it was rumored to have been delivered to teams earlier. Regardless of when teams received the memo, umpires began to check pitchers and enforcing the ban on June 21st.
Purple Row’s Justin Wick previously examined the Rockies starters and their spin rates in the games leading up to the ban, but prior to enforcement.